All about AT commands

AT commands are the instructions used to communicate directly with a modem or router. AT stands for ATtention that instructs the router about the start of a new command, that’s why every command starts with the word “AT”. For example, AT^SN, here SN is the actual command which is basically used to display the serial number of the router.

Let us have a look at the basic AT commands:-AT^RESET: Restart your routerAT^SN: Display the serial number of the routerAT^NVRDEX=50503,0,128 : Retrieve Unlock HashAT^NVRDEX=50502,0,128 : Retrieve Datalock HashAT^VERSION? : Information about the version of the modem firmwareAT^HWVER? : information about the version of the modem hardware

Check whether a router is locked or unlocked

AT^CARDLOCK?
will give the output as CARDLOCK: A,B,0
Where:
A = 1 (modem locked),
A = 2 (modem unlocked)
B = The count of remaining attempts to enter unlock code.
Your modem might show ^CARDLOCK:1, X, 0, where X is any number from 0 to 10. If 0 then you can’t enter unlock code.